Today From Bedtime Math: Skater-Mouse

Try this fun math challenge with your kids!

When it comes to mice, you can't get more famous than Mickey and Minnie. But that may soon change if a certain Australian animal trainer has his way. Yes, that picture is entirely real: Shane Willmott has been training mice to surf and skateboard for over 10 years! He says mice were born to ride boards because they have a low center of gravity, meaning they're close to the ground, and they happen to have great balance. They seem to be brave enough to enjoy it, too. Who says the smallest animals can't have the biggest thrills?  Just imagine if you flew off a ramp 10 times as tall as you!  Actually, we can do that math...

Now Here's Today's Math~

Wee ones: If a skateboarding mouse gets 3 practice "runs" down the ramp before his real run for a score, how many times does the mouse go down the ramp?

Little kids: If 8 mice go down the ramp and 3 of them "stick" their landings, how many did not have clean landings?  Bonus: If a group of 13 mice-boarders adds 1 new mouse to their skate crew, how many mice-boarders are in their group?

Big kids: How many tiny wheels do you need to build skateboards for 7 mice? (Assume 4 wheels per skateboard.)  Bonus: If you rode off a ramp 10 times as tall as you are, how high is that ramp - and if you're brave, what is it in feet and inches?

The sky's the limit: If a big group of skateboarding mice show off their tricks, and half stand on all 4 legs, a quarter of them stand on just 2 hind legs, and the rest balance on just 1 leg, how many mice are there if there are 15 legs waving in the air?

Answers:

Wee ones: 4 runs down the ramp.

Little kids: 5 mice didn't land cleanly.  Bonus: 14 mice-boarders.

Big kids: 28 wheels.  Bonus: Different for everyone...multiply your height in inches by 10 (tack a zero on the end) and if you want to go for feet and inches, divide by 12.

The sky's the limit: A quarter of the mice have 2 legs in the air, and the same number have 3 legs in the air. That means every pair of mice has 5 legs up, so for 15 legs that's 3 pairs, or 6 mice. Together they represent half the total mice, so there are 12 mice in total. For the more formal algebra: if we have Scaredy-cat mice, Medium-courage mice and Brave mice:

0S + 2M + 3B = 15 = total legs in air

However, we know S=1/2 the total, and M and B each equal 1/4 the total, so S is twice as much as either B or M: S=2B.  And of course, M and B are equal. Converting everything,

0 (2B) + 2B + 3B = 15. 5B = 15, so B =3 brave mice, and therefore 3 medium mice and 6 scaredy-cat mice.